With the popularity of smartphones, tablet computers, and other portable devices, smart portable terminals have been deeply rooted in people's lives. People desire for more convenient work or life environments using mobile terminals, and particularly via a combination of online and offline technologies. During interactive processes, authentication via user behavior may be used to ensure the safety of the processes. On the other hand, people want the processes to become more convenient. Thus, developers are looking for more flexible and safer authentication solutions using user behavior for better user experience.